Einstein’s theory helps scientists discover exoplanet

Einstein's special theory of relativity has for the first time helped a team of astronomers discover an exoplanet, the PTI reports.

"Einstein's planet", or Kepler-76b, is a "hot Jupiter" that orbits its star every 1.5 days. With its diameter is about 25 per cent more than Jupiter's and its  weight twice as much, it orbits a type F star located about 2,000 light years from earth in the constellation Cygnus.

The planet tidally locked to its star, always shows it the same face, just like the moon which is tidally locked to earth. The team uncovered strong evidence that the planet had extremely fast jet stream winds that carried the heat around it, which led to the hottest point on Kepler-76b not being the substellar point ("high noon") but a location offset by 16,093.4 km.

The effect had been observed only once before, on HD 189733b, and only in infrared light with the Spitzer Space Telescope, but this was the first instance of optical observations showing evidence of alien jet stream winds at work. The two most widely used techniques for finding exoplanets involved radial velocity (looking for wobbling stars) and transits (looking for dimming stars).

The new method looks for the simultaneous occurrence of three small effects as a planet orbits the star. Einstein's "beaming" effect causes the star to brighten as it moves toward us, tugged by the planet, and dim as it moved away.

The brightening results from photons "piling up" in energy, as also the focusing of light in the direction of the star's motion due to relativistic effects.

Meanwhile, a recent study has provided new support to Einstein's General Theory of Relativity.

There has never been any dearth of members of the scientific community looking to prove Albert Einstein's nearly 100 year-old General Theory of Relativity wrong. The monumental work describes how the elemental force of gravity helped to shape the geometry of space and time and a number of its predictions - involving phenomena like the dilation of time, the motion of bodies in free fall and the gravitational bending of light were radically different from those of classical physics.

However, despite decades of assault, Einstein's famous hypothesis has proved unshakeable, passing every test it's subjected to, including the latest one, which some scientists described as the most stringent tests ever.

A rare cosmic circumstance provided the backdrop for the test which was conducted by a group of astronomers and physicists - a rotating neutron star, or pulsar, in a tight orbit of a white dwarf star nearly 7,000 light-years from earth. 

According to scientists, the pulsar, weighing twice as much as our Sun, was the most massive neutron star ever identified, with a gravitational field over 300 billion times stronger than that on earth.

According to Dr Scott Ransom, of the National Radio Astronomy Observatory, which first spotted the pulsar system, pulsars were very, very close to being black holes, which was actually one of the very special things about this system that the pulsar, the neutron star, was one of the most massive neutron stars that had been seen, which meant that it had incredibly strong gravity. It was in orbit around a white dwarf which was much less massive.

The massive pulsar and its white dwarf companion were discovered with the Observatory's Green Bank Radio Telescope in West Virginia.

The study was led by researchers from Germany's Max Planck Institute for Radio Astronomy. The study combined data gathered by other radio and optical telescopes around the world.      

Researchers had initially hoped to prove Einstein's theory wrong, but according to Ransom their research found new evidence in the pulsar system's massive gravitational field to support Einstein's predictions.             

Ransom said, according to Einstein's Theory of Relativity as also most of the related classes of gravity theories those systems that were orbiting very, very compactly like that would give off what was known as gravitational radiation.  Basically, they caused ripples in space-time and those ripples in space-time, those waves took away some energy from the orbit; so the orbit should be shrinking with time and getting smaller, he added.

Those orbits were evidently getting smaller. According to Paulo Freire, a scientist at the Max Planck Institute for Radio Astronomy and a member of the study's research team, their radio observations of this odd binary system were so precise that they were able to measure a change in the system's orbital period of 8 millionths of a second per year, which was exactly what Einstein predicted in his theory.